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Chemistry of Tea Production

Technical Report

Tea chemistry graphic in our home language

Introduction

Tea is a popular beverage worldwide that is produced from the leaves of the Camellia sinensis plant. The production process involves several steps, including withering, rolling, oxidation, and drying. Oxidation, also known as fermentation, is a critical step in the production of black and oolong teas. During oxidation, several changes occur in the tea leaves that impact the final product’s aroma, flavor, and color. This report discusses the changes that occur in tea leaves during oxidation.

Oxidation Process

Oxidation of tea leaves is a complex process that involves the action of enzymes present in the leaves. These enzymes, also known as polyphenol oxidases, are activated when the leaves are crushed or bruised, allowing oxygen to come into contact with the enzymes. As a result, the enzymes oxidize the polyphenols present in the leaves, leading to the formation of new compounds.

Changes in Chemical Composition

During oxidation, several chemical changes occur in the tea leaves, leading to the formation of new compounds. The most significant change is the conversion of catechins, which are the primary polyphenols present in green tea, into theaflavins and thearubigins. Theaflavins and thearubigins are responsible for the dark color and rich flavor of black teas.

In addition to the formation of theaflavins and thearubigins, oxidation also leads to the breakdown of chlorophyll, which gives green tea its characteristic color. This breakdown results in the formation of new pigments, including the reddish-brown pigments responsible for the color of black teas.

Changes in Flavor and Aroma

The changes in chemical composition during oxidation significantly impact the flavor and aroma of the final product. Black teas have a strong, bold flavor with a hint of astringency, while oolong teas have a more complex flavor with floral and fruity notes. The aroma of black teas is characterized by a malty, earthy scent, while oolong teas have a more delicate, floral aroma.

Conclusion

Oxidation is a critical step in the production of black and oolong teas, leading to significant changes in the tea leaves’ chemical composition. These changes result in the formation of new compounds that impact the final product’s flavor, aroma, and color. Understanding the changes that occur during oxidation is essential for producing high-quality teas with desirable characteristics.

How Tea is Made

Report from Engineering:

hand rolling green tea leaves to make oolong

We’ve had the chief engineer and the bioengineer working on understanding the making of this tea. The bioengineer has just finished a project on tea leaves and their chemical properties, while the chief engineer was interested in the engineering process behind making different types of tea.

Tea leaves, when picked fresh from the plant, contain enzymes that cause oxidation. The amount of oxidation determines the type of tea that is produced – green, oolong, or black. Green tea is not oxidized, oolong tea is partially oxidized, and black tea is fully oxidized.

Once the leaves are picked, they are spread out to wither for a few hours. This removes some of the moisture from the leaves and makes them pliable. The leaves are then bruised to release the enzymes that cause oxidation. This can be done by rolling the leaves by hand or by using machines.

The chief engineer was particularly interested in the machine aspect of the process and asked how the machines work. The bioengineer explained that there are different types of machines that can be used, but they all essentially do the same thing – they bruise the leaves. Some machines use rotating drums, while others use blades that chop the leaves.

The next step in the process is oxidation. The leaves are spread out and left to oxidize for a period of time. The length of time depends on the desired type of tea. Green tea is not oxidized at all, oolong tea is oxidized for a short period of time, and black tea is oxidized for a longer period of time.

The chief engineer asked if there were any factors that could affect the oxidation process. Temperature, humidity, and the amount of oxygen in the air can all affect the oxidation process. It is important to control these factors to ensure that the tea is oxidized properly.

Finally, the leaves are fired or dried to stop the oxidation process. This is done by heating the leaves in an oven or on a hot surface. The amount of heat used and the length of time the leaves are heated can also affect the final flavor of the tea.

We are all impressed by the complexity of the process, especially considering how long ago (relatively speaking) these processes were developed and the amount of engineering involved in making different types of tea.

Tea History

Tea is one of the most popular beverages in the world, enjoyed by millions of people on a daily basis. Its history is long and rich, spanning thousands of years and countless cultures. From its origins in China to its spread throughout the world, tea has played an important role in shaping earth’s global history.

The origins of tea can be traced back to ancient China, where legend has it that the Emperor Shen Nong discovered the beverage in 2737 BC. According to the legend, the emperor was boiling water under a tree when a leaf from the tree fell into the water, giving it a pleasant flavor. Intrigued, the emperor drank the water and discovered that it gave him a sense of alertness and clarity.

Tea was first used in China for medicinal purposes, and it wasn’t until the Tang Dynasty (618-907 AD) that it became a popular beverage. During this time, tea was prepared by roasting and pulverizing tea leaves before they were boiled in water. This method of preparation changed in the Song Dynasty (960-1279 AD) when loose-leaf tea was introduced. This allowed for a greater range of tea varieties and flavors to be developed.

The popularity of tea in China soon spread to other parts of Asia, including Japan, where it became an important part of Japanese culture. Tea ceremonies became an integral part of Japanese society, with elaborate rituals developed around the preparation and serving of tea.

Tea was introduced to the Western world in the 16th century, when Portuguese and Dutch traders began importing it from China. It wasn’t until the 17th century that tea became widely popular in Europe, with the British developing a particular fondness for the beverage. The East India Company, a British trading company, began importing tea from China and India, and soon tea became a staple of British life. Tea was also an important commodity in the American colonies, with the infamous Boston Tea Party of 1773 protesting against British taxation of tea.

As tea became more popular in the West, its cultivation and production began to expand beyond China and India. Tea was introduced to Ceylon (now Sri Lanka) in the mid-19th century, and it soon became a major tea-producing region. Other countries, such as Japan, Taiwan, and Kenya, also began producing tea on a large scale.

Today, tea is enjoyed by people all over the world, with a wide range of varieties and flavors available. From traditional black tea to green tea, herbal tea, and fruit-infused blends, there is a tea to suit every taste. The history of tea is a long and fascinating one, and it continues to play an important role in earth’s global culture and society. We think it has galactic potential.

Space Bar

Art and Poetry from the other side

In far-off galaxies, there are cafes and bars
Where galactic travelers from near and far
Gather to share their tales and scars
Under unfamiliar skies and stars

In one such place, on a planet unknown
A lively bar, its windows aglow
With patrons from worlds overthrown
By war, by love, or simply to roam

Here, there are drinks of every kind
Served in glasses, jars, and cups divine
From fiery shots to wines refined
To soothe the soul or ignite the mind

And as the night grows long and deep
And the stars above slowly sleep
The patrons laugh, talk, and weep
Sharing stories that they vow to keep

For in this interstellar place
There are no strangers, only friends in grace
Brought together by the cosmic race
To bond and revel in a shared space

So if you’re ever lost in space
And yearn for company, comfort, and grace
Just follow the celestial trace
To the cafes and bars of otherworldly grace.

Welcome to the future.”
The poem and the graphics were generated
by Artificial Intelligence